Awesome reference on OLTP & OLAP, and data warehousing in general. Thanks.
On Tue, Jun 26, 2012 at 11:51 PM, Balasubramaniam Mohan <[email protected]>wrote: > IMHO based on experience, it is better the OLTP (online transaction > processing) and OLAP (Online Analytical Processing) dbs remain separate and > it has been well thought out in the case of ofbiz for the following valid > reasons. > > - OLTP dbs serve the transactional nature of business (orders, invoices, > etc) and requires very rapid response time for a large set of users. > Whereas OLAP is exploratory/discovery/predictive based and often results in > huge data sets being processed for analytics purposes. > > - most importantly the way the data model is done for OLTP and OLAP are > quiet different while the former is highly normalised (3NF) the later is > denormalised (dimensional-star schema). > > - Traditionally for fast response to a large set of users historical data > (say 10 years) is not stored in the OLTP. It is transferred to an archive > from where the OLAP uses for any kind analytics purposes. > > For more information on the same, please take a close look at the url at > http://datawarehouse4u.info/OLTP-vs-OLAP.html > > Hope this helps. > > Regards > On Wed, Jun 27, 2012 at 6:59 AM, BJ Freeman <[email protected]> wrote: > > > if you don't use olap, then you can deacivate the ECA(s) that triggers > > warehousing data. > > In my caee the BI DB is on a seperate server I have a special app that is > > used with it before ofbiz. > > > > Mike sent the following on 6/26/2012 2:02 PM: > > > > Thanks for the responses and clarifications. It sounds like that it's > not > >> a big deal if these are combined temporarily. > >> > > > > BJ, I thought for sure that if there is no OLAP database then the > >> ecommerce > >> module produces errors. > >> > >> However, it does help when you continually blow away the database and > >> reload it [grin]. > >> > >> On Tue, Jun 26, 2012 at 9:34 AM, Jacopo Cappellato< > >> jacopo.cappellato@hotwaxmedia.**com <[email protected] > >> > >> wrote: > >> > >> Mike, > >>> > >>> there are several good reasons for maintaining a separate olap > database; > >>> I > >>> am pretty sure that you will find plenty of information on the web. > >>> However, in the process of making the codebase slimmer and easier to > >>> maintain and configure, we have a plan to pull out some of the > components > >>> from the framework (and from the core distribution of OFBiz) and let > them > >>> evolve as pluggable and optional components; the "bi" component and the > >>> "birt" components are probably the next ones that will be moved out; at > >>> that point, if you are not interested in these datawarehouse features > and > >>> if you will use the default distribution, you will not have to worry > >>> about > >>> the additional database. > >>> As regards multitenancy implemantation, it will probably undergo under > >>> some serious architectural review, but I can't tell you, at this point, > >>> what will be the output of this. > >>> > >>> Kind regards, > >>> > >>> Jacopo > >>> > >>> On Jun 26, 2012, at 6:10 PM, Mike wrote: > >>> > >>> Here is something that has always bugged me about the OFBiz setup, > and I > >>>> was hoping that an OFBiz old-timer can please explain why the above > >>>> databases, by default, are configured as separate databases. > >>>> > >>>> I can see, in theory, why TENANT is separate. > >>>> > >>>> In the entityengine.xml, olap and tenant are separate databases. Is > >>>> > >>> there > >>> > >>>> any reason why the tables configured by these two databases, during > >>>> > >>> initial > >>> > >>>> deployment, can't be incorporated into the main ofbiz database? > >>>> > >>>> OLAP tables: > >>>> public | currency_dimension | table | bigfish > >>>> public | date_dimension | table | bigfish > >>>> public | inventory_item_fact | table | bigfish > >>>> public | product_dimension | table | bigfish > >>>> public | sales_invoice_item_fact | table | bigfish > >>>> public | sales_order_item_fact | table | bigfish > >>>> > >>>> TENANT tables: > >>>> public | tenant | table | bigfish > >>>> public | tenant_data_source | table | bigfish > >>>> > >>>> The reason I ask is when you are configuring the DB as external to the > >>>> running OFBiz java process (not 127.0.0.1, and NOT derby), you now > have > >>>> > >>> to > >>> > >>>> create and maintain 3 databases if you want to externalize the DB. I > >>>> > >>> would > >>> > >>>> rather just have to worry about a single database to replicate and > >>>> > >>> backup. > >>> > >>>> > >>>> The multi-tenant feature of OFBiz is rather an advanced feature that > >>>> most > >>>> folks are not going to use, and in the event of going that route > >>>> (multi-tenant), I could then externalize this database if necessary. > >>>> > >>>> Regarding OLAP, and why it is defined as a separate database is a real > >>>> mystery to me. Can anyone please explain why it MAY be dangerous to > >>>> > >>> merge > >>> > >>>> the above tables into the main OFBiz database? > >>>> > >>>> Thanks > >>>> > >>> > >>> > >>> > >> >
